A board may need a mux controller to stay as-is for a while longer, e.g.if setting the normally preferred idle state destroys booting.

The mechanism provided here is not perfect in two ways.1. As soon as the mux controller is registered, some mux consumer can access it and set a state that destroys booting all the same.2. The mux controller might linger in a state that is not the preferred idle state indefinitely, if no mux consumer ever selects and then deselects the mux.--- drivers/mux/core.c | 3 +++ include/linux/mux/driver.h | 4 ++++ 2 files changed, 7 insertions(+)

Untested -> no sign-off, and I'm also really unsure about it because ofthe imperfections mentioned in the commit message.

diff --git a/include/linux/mux/driver.h b/include/linux/mux/driver.hindex 35c3579c3304..21cf6041a962 100644--- a/include/linux/mux/driver.h+++ b/include/linux/mux/driver.h@@ -36,6 +36,9 @@ struct mux_control_ops { * @states: The number of mux controller states. * @idle_state: The mux controller state to use when inactive, or one * of MUX_IDLE_AS_IS and MUX_IDLE_DISCONNECT.+ * @init_as_is: Set to true to have the core leave the mux controller+ * state as-is until first selection. If @idle_state is+ * MUX_IDLE_AS_IS, @init_as_is is irrelevant. * * Mux drivers may only change @states and @idle_state, and may only do so * between allocation and registration of the mux controller. Specifically,@@ -50,6 +53,7 @@ struct mux_control {